Fifth wheel plate assembly



Dec. 16, 1969 H. s. WILLE 3,484,124

FIFTH WHEEL PLATE ASSEMBLY Filed May 25, 1967 nited States Patent 0 3,484,124 EiFlH WHEEL PLATE ASSEMEELY Herbert 5. Wills, Homewood, llL, assigncr to Pullman Incorporated, (Ihicago, ill, a corporation of Delaware Filed May 25, 1967, Ser. No. 641,221 Int. Cl. F1613 9/00 lU.S. Cl. 28720 2 Ciaims ABSTRACT OF THE DiSCLOSURE A fifth wheel plate assembly particularly adapted for use on a collapsible stanchion for hitching a semi-trailer to a railway car by means of the kingpin depending from the underside of the semi-trailer. The semi-trailer kingpin includes a shank of substantially constant diameter along its length and a peripheral groove of lesser diameter than the shank intermediate the ends thereof which defines a cylindrical flange end. The fifth wheel plate assembly includes a plate of generally rectangular contour having a kingpin entry slot extending from one edge of the plate and terminating in the center of the plate in a substantially semicircular end wall. Formed on the underside of the plate is a hollow cylindrical locking chamber having a center eccentrically disposed with respect to the center of the semicircular end wall. The chamber includes a bottom support plate for supporting and retaining the locking jaw therein. The bottom plate is vertically spaced from the upper surface of the plate a distance substantially equal to the vertical distance of the base of the kingpin to the upper surface of the circular flange. The bottom support plate is formed with a kingpin entry slot aligned with the fifth wheel plate entry slot and is terminated in a semicircular end wall coaxially disposed with the entry slot circular end wall but having a diameter less than the latter so as to provide a flange which overlies the flanged end of the kinpin. The circular locking jaw is turnably disposed in the cylindrical chamber and has a U-shaped opening which is aligned with the entry slots so that when the kingpin is introduced therein the locking jaw is turned to embrace the kingpin and retain the latter locked within the chamber. Associated with the locking jaw is a latching plunger which retains the former in the locked position until released.

SUMMARY OF THE INVENTION The present invention provides a fifth wheel plate assembly particularly adapted for use on a collapsible stanchion used for hitching a semi-trailer on a railway car which is movable between an erect operative position for hitching a semi-trailer thereto and a collapsed stored position on the deck of the railway car. The fifth wheel plate assembly includes a locking jaw chamber in which a bottom plate serves as a means for retaining the kingpin from vertical displacement relative to the fifth wheel plate when the trailer is hitched thereto. This structure permits the overall height of the fifth wheel plate assembly to be reduced to a minimum whereby the plate may be maintained at a minimum distance from the deck of the railway car.

BRIEF DESCRIPTION OF THE DRAVVTNGS FIG. 1 is a bottom plan view of the fifth wheel plate embodying the principles of the present invention;

FIG. 2 is a longitudinal cross sectional upright view of the fifth wheel plate taken generally along the lines 2-2 of FIG. 1, and showing the locking aw in its locked position; and

FIG. 3 is a transverse sectional upright View taken generally along the lines 33 of FIG. 1.

3,484,124 Patented Dec. 16, 1969 ice DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, there is shown a fifth wheel plate assembly 1% of the type which is particularly adapted for use on collapsible stanchions used on railway cars for hitching semi-trailers thereon and includes generally a plate 11 on the underside of which there is provi ed a kingpin locking jaw chamber 12 having turnably disposed therein a locking jaw 13. Engage'able with the locking jaw 13 is a latching arrangement 14 for retaining the locking jaw in the locked position thereof to retain a semi-trailer kingpin K against horizontal displacement.

The fifth wheel plate 1%, as shown, is formed as a casting and includes a. web 16 having an upper planar support surface 17 on which the underside of the semi-trailer is adapted to rest when supported thereon. Projecting from the underside of the web 15 is a plurality of stiffening or reinforcing flanges 13 including two pair of spaced webs 19l? each having means for receiving a pin for attaching the fifth wheel plate to a stanchion.

Formed on the right side of the web 16 as viewed in FIG. 1 is a kingpin entry slot 21 which is adapted to receive and guide the kingpin K to the locking jaw 13. To this end the entry slot includes spaced parallel surfaces 22 22 which merge with inwardly tapering surfaces 23-23. Extending from the inner ends of the inwardly tapering surfaces 23-43 are spaced parallel guiding surfaces 2424 which engage the kingpin K. The web entry slot at its inner end terminates in a substantially semicircular end wall 26 having a center which is located substantially midway between the side edges of the web 16.

The kingpin K, as shown, is formed from a cylinder or shank S of which the base or top is fixed to the underside of a semi-trailer (not shown) and is of substantially constant diameter along its length. Formed in the shank S is a groove G which extends intermediate the ends thereof so that the lower or terminal end forms a terminal flange F.

The kingpin locking jaw chamber 12 comprises a hollow cylinder chamber 27 formed on the underside of the plate casting 11 with the center thereof transversely displaced from the center of the semicircular end wall 26 of the entry slot 21 but in longitudinal alignment therewith, as shown in FIG. 1. Forming a base of the locking jaw chamber is a bottom support plate 28 which is suitably fastened to the underside of the plate by means of screws 29 or the like. The support plate 28 is vertically spaced from the upper surface of the web 16 a distance substantially equal to the vertical space from the base of the kingpin K to the upper surface of the terminal peripheral flange F. In this manner the plate 28 serves as a kingpin retention means preventing vertical displacement of the kingpin K from the lockin jaw 13, as more fully to be explained hereinafter. Formed in the forward edge of the bottom support plate is an entry slot 31 including a pair of parallel walls 32-32 spaced substantially equal to the parallel walls 24 of the fifth wheel plate entry slot 21. The inner ends of the parallel walls 3232 are joined by a semicircular end wall 33 having a center disposed coaxially with the center of the base plate semicircular end wall 26. To retain the kingpin K against a ertical displacement out of the slot the support plate semicircular end wall 33 is formed of lesser diameter than the base plate end wall and substantially equal to the diameter of the grooved section G of the kingpin K. Thus, as shown in FIG. 2, the semicircular end wall overlies the peripheral flange to retain the latter against vertical displacement. For guiding the kingpin K into the base plate entry slot the underside of the base plate adjacent the entry slot formed with chamfered legs 33a 3 which are engageable with the upper surface of the peripheral flanged end P of the kingpin K to guide the latter downwardly beneath the semicircular end wall 33.

The locking jaw 13 is formed as a disc 34 of substantially the same diameter as the cylindrical locking jaw chamber 12 and of a thickness approximately the same as the height of the chamber 12. Formed in the disc 34 is a U-shaped opening 36 terminating at its inner end in a circular bight portion 37 having a diameter substantially equal to the diameter of the kingpin shank S so as to be capable of embracing the same. The locking jaw 13 is turnable from a position in which the U-shaped opening 36 is located for engagement with the kingpin K as the latter is guided thereto through the entry slots 21 and 31. The U-shaped opening 36 is positioned such that the kingpin K rotates the jaw 13 to the locked position, as shown in FIG. 1.

Angularly spaced from the U-shaped opening 36 is a latching notch 39 which receives a spring biased latching bar 41 of the latch assembly 14 which serves to hold the locking jaw 13 in its locked position. The spring biased latch assembly includes a release assembly which may be actuated either manually or automatically by stanchion operated means to retract the plunger 41 from the notch 31. For a more detailed description of the latching assembly and its operation, reference is made to US. Patent No. 3,358,955, issued Dec. 19, 1967, assigned to the assignee of the present invention. Upon retraction of the latching bar 41, the locking jaw 13 is free to rotate as the kingpin is withdrawn during removal of the semi-trailer from the plate assembly 10.

I claim:

1. A fifth wheel plate for hitching a semi-trailer to a stanchion by means of a kingpin depending from the underside of the semi-trailer and wherein said kingpin includes a shank of substantially constant diameter along its length and a peripheral groove of lesser diameter size than said shank intermediate the end thereof and defining a terminal flange, said fifth wheel plate comprising an upper plate member, a kingpin entry slot extending from one end of said upper plate member and terminating in a generally arcuate shaped end wall, a locking jaw chamber located on the underside of said upper plate member, said chamber including a bottom plate member vertically spaced from the upper surface of said upper plate member a distance substantially equal to the vertical distance from the base of the kingpin to the upper face of the said terminal flange, said bottom plate member having a kingpin entry slot and terminating in a generally arcuate end wall coaxially disposed relative to the upper plate member end wall and having a diameter less than said upper plate member end wall, the diameter of the bottom plate being approximately equal to the diameter of said groove of said kingpin so as to overlie said terminal flange, an annular locking jaw turnably disposed in said locking jaw chamber and having a slotted opening sized to embrace said kingpin, wherein bottom plate member entry slot includes tapered surfaces formed on the underside thereof to guide said kingpin terminal flange beneath said bottom plate semicircular end wall.

2. A fifth wheel plate assembly for hitching a semitrailer to a stanchion by means of a kingpin depending from the underside of the semi-trailer and wherein the kingpin is of the type having a shank of substantially constant diameter along its length and a peripheral groove of less diameter size than the shank intermediate the ends of the shank to define a lower terminal fiange and an upper shank portion, said fifth wheel plate assembly comprising: an upper plate having a kingpin entry slot extending in from one end of said upper plate and terminating in a generally arcuate end wall for reception of the kingpin shank therethrough, a bottom plate vertically spaced below the upper surface of said upper plate a distance substantially equal to the vertical distance from the base of the kingpin to the upper face of the terminal flange and defining with the upper plate a locking jaw receiving chamber between the plates, an annular locking jaw turnably disposed in said locking jaw chamber and having a slotted opening of a dimension to receive the upper shank portion of the kingpin and being generally vertically aligned with the arcuate end wall of the upper plate for confining the upper shank portion of the kingpin in the upper plate slot and in locking jaw opening above the bottom plate, the bottom plate having a kingpin entry slot terminating in a generally arcuate end wall coaxially disposed relative to the upper plate end Wall and having a diameter less than said upper plate end wall to define a horizontal lip portion extending into the groove between the-upper shank portion and lower kingpin flange for engagement with the lower shank portion for limiting upward movement of said kingpin, and said bottom plate being provided with entrant portions for guiding the lower flange of the kingpin underneath said bottom plate portion.

References Cited UNITED STATES PATENTS 4/1937 King 28O--435 8/1966 Ferris 287-20 US. Cl. X.R. 

